Causal relationship between dementia and delirium: Insights from a bidirectional two-sample Mendelian randomization...

Area of Science:

• Neurology
• Genetics
• Epidemiology

Background:

• Dementia is a known risk factor for delirium in elderly patients with hip fractures.
• The precise causal link between dementia and delirium remains incompletely understood.

Purpose of the Study:

• To investigate the bidirectional causal relationship between dementia and delirium using genetic data.
• To provide genetic evidence for the etiological connection between these two conditions.

Main Methods:

• Bidirectional Mendelian randomization (MR) analysis was performed.
• Multiple MR methods including Inverse-variance weighted (IVW) and weighted median were employed.
• Statistical tests for heterogeneity and horizontal pleiotropy were conducted to ensure robustness.

Main Results:

• Forward MR analysis showed dementia (unclassified, Alzheimer's disease, dementia with Lewy bodies) significantly increases delirium risk.
• Reverse MR analysis indicated delirium increases the risk of unclassified dementia and vascular dementia.
• Multivariable MR analysis validated these significant bidirectional associations.

Conclusions:

• This study provides robust genetic evidence supporting a causal relationship between dementia and delirium.
• Findings suggest dementia may predispose individuals to delirium, and conversely, delirium may elevate the risk of developing dementia.